The present invention relates to closing openings in a vessel or other body cavity. More specifically, the present invention relates to an expandable closure device having a barrier coating layer to delay expansion of the device when placed into the body cavity.
There are a wide variety of procedures which require gaining internal access to blood vessels or other body cavities. Many such procedures also require the insertion of treatment devices into the blood vessel or body cavity. Many of these procedures utilize accessible arteries as entry points for the treatment devices. For example, some such arteries include the femoral artery or subclavian artery. There are also a wide variety of procedures which gain access to other body cavities in a minimally invasive fashion.
One problem which must be addressed during these procedures is how to seal or close the opening in the blood vessel or other body cavity once the treatment procedure has been completed. Some prior techniques include simply applying pressure to the opening until it seals itself sufficiently that the pressure may be released. However, this technique often requires that pressure must be consistently applied for an undesirable amount of time after the procedure. Similarly, this type of technique can require a patient's hospitalization to be extended until the treating physician is certain that the closure is complete.
Other techniques have involved suturing the wall of the vessel or body cavity itself. This has typically required the physician to peel back a rather large portion of the tissue surrounding the puncture in order to gain sufficient access to the blood vessel or body cavity that it may be sutured adequately. This can be an undesirably time consuming procedure, and it can result in significant discomfort to the patient.
Still other techniques have involved the insertion of embolic materials adjacent the puncture. Of course, this carries with it its own difficulties. For instances, it is desirable that the embolic material not be placed within a blood vessel or body cavity because this can result in an embolus forming within the blood vessel or body cavity. Similarly, however, it is desirable that the embolic material not be located to far proximal of the puncture because this can result in the blood vessel or body cavity bleeding into the interstitial space proximal of the opening in the blood vessel or body cavity, but distal to the embolic material.
Another technique used to close the opening in the blood vessel or other body cavity once the treatment procedure has been completed is to insert an expandable hemostatic member into the opening. For example, the member can be at least sponge-like material which expands to fill the opening thereby close the opening. However, it can be difficult to properly place the expandable member in the opening because in its expanded state, the member has a size which is greater than that provided by the opening.